2157131 has 2 divisors, whose sum is σ = 2157132. Its totient is φ = 2157130.

The previous prime is 2157121. The next prime is 2157149. The reversal of 2157131 is 1317512.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2157131 is a prime.

It is a super-2 number, since 2×2157131² = 9306428302322, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (2157121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1078565 + 1078566.

It is an arithmetic number, because the mean of its divisors is an integer number (1078566).

2^2157131 is an apocalyptic number.

2157131 is a deficient number, since it is larger than the sum of its proper divisors (1).

2157131 is an equidigital number, since it uses as much as digits as its factorization.

2157131 is an evil number, because the sum of its binary digits is even.

The product of its digits is 210, while the sum is 20.

The square root of 2157131 is about 1468.7174677248. The cubic root of 2157131 is about 129.2088238853.

The spelling of 2157131 in words is "two million, one hundred fifty-seven thousand, one hundred thirty-one".